The gang's all here in 'The Avengers' ✭✭✭

The culmination of everything ever written, produced or imagined in the known universe, or something like that,"The Avengers"bunches together Iron Man, Captain America, The Hulk, Thor, the leather-clad assassin Black Widow, the lethal archer Hawkeye and the superheroes’ one-eyed wrangler, Nick Fury, for 143 minutes of stylish mayhem in the service of defeating Thor’s malevolent brother, the god Loki, who hails from the interstellar world known as Asgard (access through wormhole only), and who yearns to conquer Earth with an all-powerful blue energy cube called the Tesseract.

So is this Marvel Comics franchise alumni reunion a full-on Hulk smash? Financially, yes, most likely. ("The Avengers" is already killing ‘em overseas.) If the film is more solid and satisfying than terrific, so be it. Cleverly, writer-director Joss Whedon combines and recombines its various intramural rivalries. If you were a fan of two or three or more of the movies directly feeding into this one, you’re already planning on seeing "The Avengers."

Seeing it in 2-D, the movie played well enough. Catching it a second time this week, in 3-D, with a raucous, eager crowd, provided that little extra something that lifted the experience up a level. While 3-D isn’t crucial to your engagement with “The Avengers,” it helps. The Cinematographer Seamus McGarvey’s palette, nice and bright, compensates for the dimness factor that comes with putting on those ill-fitting glasses. Compare the scenes set on the planet Asgard in Whedon’s film with the early, turgid chunks of director Kenneth Branagh’s “Thor,” and you have the difference between a sleekly burnished surface and murk.

In this corner: the familiar faces. Top-billed and serenely confident in his underplaying, Robert Downey Jr. returns as industrialist Tony Stark, whose "Iron Man 2" colleague Black Widow, played by Scarlett Johansson, joins the fight against Loki (slithering Tom Hiddleston, back from “Thor”). Thor himself, played by Chris Hemsworth, comes ‘round once again with his boomerang hammer. Chris Evans, aka Captain America, re-enters the ring, a symbol of retro-nostalgia and stalwart God-fearing patriotic values. Samuel L. Jackson, who has dipping in and out of these movies since the first “Iron Man” four years ago, finally gets some serious screen time, as does, more surprisingly, Clark Gregg’s Agent Coulson. I like Gregg; with all these outre costume-party characters swanning around and cleaning clocks, it’s nice to have a Cheshire cat of a character man get his due.

And in this corner: the new guys. Chiefly there's Mark Ruffalo as Dr. Bruce Banner, better known as the Hulk. Previously the Hulk has been played by Lou Ferrigno on TV and, in feature films, Eric Bana and Edward Norton. As with Downey, Ruffalo doesn't have to do much to hold the screen; unlike Downey, Ruffalo finds ways to do so without resorting to an artful but narrow range of throwaway sarcasm. Jeremy Renner's Hawkeye, deadly with the straight-to-the-eye arrows, cements 2012 as The Year of the Bow, arriving to the Marvel movies as he has so soon after"The Hunger Games."

"The Avengers" is essentially an extended action sequence interrupted by an extended soul-search in the middle. On board their invisible flying aircraft carrier known as the Helicarrier, our heroes, the agents of the covert S.H.I.E.L.D. peacekeeping club , keep breaking down into rivaling subgroups at the wily behest of Loki, who's like the most evil gym coach ever. Whedon's narrative task with "The Avengers"? Finding the best, most propulsive ways to pit Thor against Loki; the Hulk (wittily delayed in terms of the characters' Big Entrances) against Black Widow; Black Widow against the evil version of Hawkeye; and so forth.

The "Transformers 3"scale of the urban carnage in the final hour of "The Avengers" is a long way from the relative size, and contrasting comic tone, of the first "Iron Man," one of my two faves (the other being "Captain America") in this corner of the comic-book movie universe. When "Iron Man" clicked with audiences four summers ago, the reasons were both clear and refreshing: Downey and Gwyneth Paltrow, who returns here, had unusually potent comic chemistry, and although director Jon Favreau (one of the producers on "The Avengers") wasn't a genius at staging action, he knew how to establish a tone and stick to it.

So does Whedon, though I surely do wish someone other than Alan Silvestri had composed the music; this stuff is so generic, the movie would actually be better off with no music and someone in voiceover merely saying "And here we'll have some stirring triumphal nonsense like the stuff you heard three scenes ago." Little matter, at least to the box office. Whedon's both a wiseacre — Stark at one point refers to Thor as "Point Break," referencing his Patrick Swayze surfer locks — and a sincere devotee of Marvel's durable, malleable ensemble of lugs and indestructibles, introduced as a group in 1963. The ending, which won't come as a surprise, sets us up for a sequel. Just as Stark and Loki represent two preening, egomaniacal sides of the same coin, "The Avengers" is both a culminator and a set-up for more, more, more.